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Biomedical subjects

X Weng

Publications and source records attributed to X Weng.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Detection of intrauterine transmission of human cytomegalovirus by nested polymerase chain reaction].

OBJECTIVE: Using nested polymerase chain reaction (PCR) to detect Intrauterine transmission of human cytomegalovirus (HCMV). METHODS: Ninety one cases of pregnant women were devided into three groups according to their gestational stages. In the first and second trimesters, they terminated pregnancy voluntarily. HCMV-DNA in maternal and cord blood as well as placenta were detected respectively by nested PCR. RESULTS: In the first trimester, 20 out of 30 cases were infected, Intrauterine transmission occured in 8 of the 20 infected mothers (HCMV-DNA were found in the chorionic villus). In the second trimester, 21 out of 30 cases were infected, 7 of them transmitted HCMV to their fetus through placenta. In this term, the placenta infection rate is 40% (12/30). In the third trimester, 23 out of 31 cases women infected HCMV, 18 of them transmitted HCMV to their fetus through placenta, the placenta infection rate is 66.67% (20/30). The congenital infection rate is 58.06% (18/31), much higher than the reported levels marked by cord sera IgM and (or) infants viremia. CONCLUSIONS: HCMV transmitted from mother to infant mainly through placenta. Nested PCR provides a valuable method that can detected virus infection not limited by virus reproduction state and human immuno-reaction ability.

Cytomegalovirus↗
PubMed1995

[Clinical observation on perinatal Chlamydia trachomata infection].

OBJECTIVE: To screen antigen of genital chlamydia trachomata (CT) in pregnant women and to study its clinical characteristics, treatment and transmission to the newborns. METHOD: Monoclone antibody immuno-fluorescence was employed in assaying. RESULTS: Positive incidence of CT infection during pregnancy was 86 cases (26.88%), of whom 47/64 cases (73.44%) treated with traditional Chinese herbs for 2 weeks became negative. The other 22 were not treated because either they were too near to term (21 cases) or had local allergic reaction (1 case). Incidence of positive CT in newborns from untreated mothers was 81.82%, treated and became negative was 23.40%, treated but still positive was 88.24%. CONCLUSION: Antenatal treatment is of importance in preventing intrapartum transmission of CT from mother to child. The data indicated that treatment with traditional Chinese herbs was effective.

Adult↗
PubMed1995

[A preliminary observation on the effects of inhaled nitric oxide on bronchial asthma].

Nitric oxide (NO) is a vasodilator as well as a bronchodilator. In order to estimate the therapeutic effects of NO on bronchial asthma, 10 patients in acute exacerbation stage were selected for this study. 40 ppm NO was inhaled for 20 minutes. The clinical stage and pulmonary function were evaluated instantly. The results showed that subjective symptoms were relieved and wheezing rales decreased to a different extent, FEV1 and PEF improved significantly (P < 0.05). It is suggested that low concentration NO inhalation can be used as a therapeutic measure for bronchial asthma.

Administration, Inhalation↗
PubMed1994

High-resolution crystals and preliminary X-ray diffraction studies of a catalytic RNA.

High-resolution single crystals of a catalytic RNA molecule derived from the sequence of the satellite RNA of tobacco ringspot virus have been obtained. The unit-cell volumes of the RNA crystals vary depending on the crystallization conditions and temperature. The best crystal form, when flash frozen, has space group P1 with unit-cell dimensions a = 53.08, b = 71.81, c = 28.03 A, alpha = 98.43, beta = 104.32 and gamma = 74.54 degrees. This form diffracts to a resolution of 2.4 A. A heavy-atom derivative search is in progress.

Journal Article↗
PubMed1994

Short- and long-term prognosis after acute myocardial infarction in Chinese men and women.

Most, but not all, studies in Western countries have indicated that women have a higher mortality than men after an acute myocardial infarction, but this has not been well documented in the developing world. The authors studied 601 male and 294 female myocardial infarction patients, aged 26-94 years, admitted to a city hospital in Beijing, China, between 1974 and 1986. A total of 745 (98.8%) of the cohort of 754 who survived past their initial hospitalization were followed up in 1988. Compared with their male counterparts, female myocardial infarction patients were older (63.4 vs. 58.1 years) and had a higher prevalence of tachycardia (heart rate, > or = 110 beats/minute), rales, New York Heart Association class III or IV, and heart block, but a lower prevalence of smoking and white collar occupation (all p < 0.01). The mortality within 28 days of their myocardial infarction was higher in women than in men, mainly in the group whose age was less than 60 years (20.4% vs. 7.1%, p < 0.001). The greater risk of short-term mortality in women persisted even after adjustment for age, history of stroke and hypertension, tachycardia on admission, anterior infarction, Killip class III or IV, and arrhythmia (relative odds = 1.74, 95% confidence interval 1.17-2.60). The 10-year total cumulative mortality in persons who survived the first 28 days following their myocardial infarction was 51.1% for women and 35.9% for men (log rank p = 0.002). After adjustment for age, this difference was not statistically significant (p = 0.3). Our results suggest that, in Beijing, women have a higher short-term mortality after myocardial infarction compared with men.

Adult↗
PubMed1994

Application of internal fixation in the treatment for tuberculosis of the spine.

This is a study of 18 patients who had surgical treatment for spinal tuberculosis. All patients were admitted with the spinal tuberculosis and treated with a combination of anterior debridement and bone graft with posterior internal fixation using the Luque or Dick technique. The patients were able to walk within a few days postoperation. Three to seven years follow-ups show no recurrence, kyphosis and/or solid fusion.

Adolescent↗
PubMed1993

Crystal structure of human annexin I at 2.5 A resolution.

cDNA coding for N-terminally truncated human annexin I, a member of the family of Ca(2+)-dependent phospholipid binding proteins, has been cloned and expressed in Escherichia coli. The expressed protein is biologically active, and has been purified and crystallized in space group P2(1)2(1)2(1) with cell dimensions a = 139.36 A, b = 67.50 A, and c = 42.11 A. The crystal structure has been determined by molecular replacement at 3.0 A resolution using the annexin V core structure as the search model. The average backbone deviation between these two structures is 2.34 A. The structure has been refined to an R-factor of 17.7% at 2.5 A resolution. Six calcium sites have been identified in the annexin I structure. Each is located in the loop region of the helix-loop-helix motif. Two of the six calcium sites in annexin I are not occupied in the annexin V structure. The superpositions of the corresponding loop regions in the four domains show that the calcium binding loops in annexin I can be divided into two classes: type II and type III. Both classes are different from the well-known EF-hand motif (type I).

Amino Acid Sequence↗
PubMed1993

Expression of alpha 1, alpha 5, and gamma 2 GABAA receptor subunit mRNAs measured in situ in rat hippocampus and cortex following chronic flurazepam administration.

Prolonged benzodiazepine treatment of rats results in anticonvulsant tolerance in vivo. Studies of in vitro hippocampal slices following 1 wk flurazepam administration show reduced GABA-mediated inhibition in the CA1 region, and a decrease in GABAA agonist and benzodiazepine potency to inhibit CA1 pyramidal cell-evoked responses. To investigate the molecular basis of benzodiazepine tolerance in the hippocampus, in situ hybridization techniques were used to evaluate the expression of the mRNAs for the alpha 1, alpha 5, and gamma 2 subunits of the GABAA receptor in the hippocampal formation and frontal cortex of chronic flurazepam-treated rats. A discretely localized decrease in alpha 1, but not alpha 5 or gamma 2 mRNA expression was found in the CA1 region (35-40%) and in layers II-III and IV of cortex (50-60%) 2 d after cessation of flurazepam treatment. The decrease in the expression of alpha 1 subunit mRNA in cortex is similar to that reported following other chronic benzodiazepine treatment regimens. This is the first report of a reduction in alpha 1 subunit mRNA expression in the hippocampal formation.

Animals↗
PubMed1993

Characterization of substantia nigra pars reticulata neurons based on response to iontophoretically applied GABA and flurazepam.

Previous work had suggested that neurons in the pars reticulata of the substantia nigra (SNpr) might be differentiated based on responsiveness to GABA and benzodiazepines (BZs). To evaluate this possibility, multi-barreled glass capillary assemblies were used to examine the effects of GABA and a BZ, flurazepam (FZP), on the spontaneous activity of single SNpr neurons in chloral hydrate anesthetized rats. Both FZP and GABA, as a function of increasing ejection current, decreased the rate of neuronal discharge. SNpr neurons differed according to the maximum effect of each agent. For over half of the cells, the spontaneous discharge could be inhibited at least 90% by GABA, while the maximum FZP effect in the same cells ranged from 20 to 100% inhibition. Except for 3 neurons, the maximum inhibition produced by GABA was about the same or greater than that produced by FZP. No clear anatomical segregation according to BZ effect was found.

Action Potentials↗
PubMed1993

Regulation of atrial natriuretic peptide, thromboxane and prostaglandin production by androgen in elderly men with coronary heart disease.

Several recent observations suggest that atrial natriuretic peptides (ANP) can modulate steroidogenesis in isolated rat Leydig cells and in young men. Other observations suggest that catechol estrogen can inhibit prostaglandin (PGI2) release in the endothelium, and we had found that androgen can relieve angina pectoris and improve myocardial ischemia in elderly men with coronary heart disease (CHD), possibly through relieving coronary artery smooth muscle spasm. Because ANP and PGI2 are vasoactive peptides which regulate vasomotion, there must be an interaction between steroidogenesis hormones and vasoactive peptides. We evaluated the effects of androgen (Sustanon 250) administration on plasma ANP, PGI2 and thromboxane (TXA2) levels in elderly men with CHD. Thirty 60-75-year-old men with CHD received 250 mg (1 ml) Sustanon 250 injection, and 30 age- and sex-matched CHD patients received 1 ml saline. Plasma ANP, PGI2, TXA2, estradiol (E2) and testosterone (T) were determined before injection and 3 weeks thereafter. The results showed that Sustanon 250 administration increased plasma ANP levels, decreased TXA2 and increased PGI2 levels significantly, and thereby improved the TXA2/PGI2 imbalance in CHD patients (all P < 0.01). Meanwhile, serum T levels rose (P < 0.01), but E2 levels remained unchanged, and thus the E2/T ratio decreased (P < 0.05). Our findings demonstrate that androgen exerts its regulatory role by altering plasma ANP levels and the TXA2/PGI2 ratio.

6-Ketoprostaglandin F1 alpha↗
PubMed1992

Infusion of bicuculline methiodide into the tectum: model specificity of pro- and anticonvulsant actions.

Microinjection of drugs, such as muscimol, into the substantia nigra pars reticulata (SNpr) can inhibit several types of experimental seizures. Some findings suggested that this was a result of disinhibition of neurons receiving input from GABAergic nigrotectal cells. Indeed, it was reported that bicuculline methiodide (BMI), infused into the tectal region that was reported to receive nigral input, produced an anticonvulsant effect against maximal electroshock (MES) convulsion. Since previous work had suggested that the anticonvulsant effect of intranigral muscimol depended on the particular experimental seizure used, three different experimental seizures were used in the present study to evaluate the effects of BMI infusion into the tectum. Guide cannulas aimed at the tectal region receiving nigral innervation were stereotaxically implanted in rats a week before testing. Bilateral intratectal infusions of BMI (25 ng/side) had an anticonvulsant effect against MES convulsions, confirming a previous report. In contrast, the same BMI pretreatment worsened convulsions produced by either systemic pentylenetetrazol (40 mg/kg, i.p.) or bicuculline (0.5 mg/kg, i.v.). The effects of intratectal BMI were seizure model-dependent, suggesting different functional interconnections between tectum and those pathways responsible for generalization of MES as compared to PTZ or bicuculline convulsions.

Animals↗
PubMed1992

Phenotypic and functional analysis of tumour-infiltrating lymphocytes from patients with melanoma and other metastatic cancers.

Thirty tumour specimens, among which were 17 melanomas, were cultured with recombinant interleukin-2 (IL-2) in order to produce tumour-infiltrating lymphocytes (TIL). In the melanomas, three categories of TIL were characterised. The first, containing mostly CD3+ and CD8+ cells, lysed only autologous tumour cells; the second, containing mostly CD3+ and CD4+ cells, lysed both autologous tumour cells and allogeneic cells lines; the third, with mixed phenotype although cytotoxic for K562 targets, did not kill melanoma cells. The optimal conditions for a good development of TIL were established: we found that the lymph node or cutaneous origin of the tumour was unimportant, a 2 h enzymatic treatment was optimum and that TIL grew well in AIM V serum free medium. Therefore the easiness and the reproducibility of the TIL cultures from melanoma tumour samples allows the rapid development of therapeutic trials in metastatic melanoma.

Adult↗
PubMed1992

Therapeutic effect of andriol on serum lipids and apolipoproteins in elderly male coronary heart disease patients.

The elevated estradiol/testosterone (E2/T) ratio had been proved to be a risk factor for coronary heart disease (CHD) in elderly males and to exert an adverse effect on lipid metabolism. We conducted a randomized cross-over study to determine the effect of Andriol, a new androgenic preparation, on plasma lipids and apolipoproteins. The results showed a significant difference in most parameters between patients receiving Andriol and the control group: in the former, serum T level was elevated significantly (P < 0.001), E2 level was unchanged (P > 0.05) and the E2/T ratio was reduced (P > 0.05). Blood levels of total cholesterol (TC) and triglyceride (TG) were lowered dramatically (P < 0.001) and high density lipoprotein cholesterol (HDL-ch) was raised (P < 0.05), but apolipoprotein-AI (APO-AI) and B (APO-B) levels remained unchanged. No obvious side effect was observed in those who took Andriol.

Aged↗
PubMed1990

[Preliminary study on leprosy subclinical infection and its sero-epidemiology].

The detection of subclinical infection with M. leprae among 360 household contacts of leprosy and 95 healthy controls was conducted with PGI-ELISA in leprosy-endemic areas. The relationship of age at infection, and onset with epidemic trends was explored basing on the distribution features of subclinical infection with M. leprae in household contacts of leprosy. In addition, the multiple linear regression was used to analyse the factors affected the level of antibody in leprosy.

Adolescent↗